BTF3a/b CRISPR Activation Plasmid (h): sc-403520-ACT

BTF3 encodes basal transcription factor 3, which produces the BTF3a and BTF3b isoforms that participate in RNA polymerase II–dependent transcription initiation and broader regulation of gene expression. BTF3 also functions as a nascent-polypeptide–associated factor, coupling transcriptional programs to co‑translational processes that influence proteostasis and cellular stress responses. Through these roles, BTF3 impacts fundamental pathways controlling proliferation, apoptosis, and adaptation to proteotoxic stress. Altered BTF3 expression has been reported in multiple cancers and other disorders characterized by dysregulated transcription and protein homeostasis, supporting its utility as a mechanistic node for pathway interrogation.

BTF3a/b CRISPR Activation Plasmid (h) provides a targeted, non-destructive approach to upregulating endogenous BTF3 expression without altering the underlying DNA sequence.

BTF3a/b CRISPR Activation Plasmid (h) is a three-plasmid synergistic activation mediator (SAM) system engineered for highly efficient, site-specific transcriptional upregulation of the BTF3 locus in human cell lines. The system is built around a catalytically inactive Cas9 (dCas9) carrying two inactivating mutations (D10A and N863A) that eliminate nuclease activity while preserving DNA binding. This dCas9 is fused to VP64, a potent transcriptional activator, and is co-expressed with a blasticidin resistance gene for selection. The second plasmid encodes the MS2-p65-HSF1 fusion protein, a secondary activator complex that works in concert with dCas9-VP64, alongside a hygromycin resistance gene. The third plasmid encodes a target-specific 20 nt sgRNA fused to two MS2 RNA aptamers that recruit the MS2-p65-HSF1 complex to the activation site, accompanied by a puromycin resistance gene. The three plasmids are delivered at a 1:1:1 mass ratio for balanced expression of all system components.

Once assembled at the target locus, the SAM complex binds within approximately 200 bp upstream of the BTF3 transcriptional start site, where VP64, p65, and HSF1 act in concert to recruit transcriptional machinery and drive upregulation of endogenous BTF3a/b expression. Unlike nuclease-active Cas9, dCas9 does not introduce double-strand breaks or modify the genomic sequence, preserving the native BTF3 locus and enabling the study of BTF3a/b-dependent transcriptional responses at the endogenous locus, making it a valuable tool for functional studies, target gene identification, and the modeling of BTF3a/b pathway restoration in tumor cells with silenced or reduced BTF3 expression.

For Research Use Only. Not Intended for Diagnostic or Therapeutic Use.